Radial pump



- March 23, 1965 w, w ER 3,174,436

' RADIAL PUMP Filed Nov. 23, 1962 FIG. 1

4 Sheets-Sheet 1 I il a? i INVENTOR. WILLIAM F. MNNER vBY/% AT TORNEYSMarch 23, 1965 w. F. WANNER 3,174,436

' RADIAL PUMP File d Nov. 25, 1962 4 Sheets-Sheet 4 Z1 4 FIG. 1.!

INVENTOR. 'W/LuAu 1-? Wk/viva:

A T TOFPNE Y8 United States Patent 3,174,436 RADIAL William F. Wanner,Minneapolis, Minn., assignor to Sceger-Wanner Corporation, Minneapolis,Minn, a corporation of Minnesota Filed Nov. 23, 1962, Ser. No. 239,606 6Claims. ((ll. 103-174) This invention relates to multiple cylinderradial pumps. More particularly, this invention relates to a new andvery useful four-cylinder, positive displacement type radial pump and tointegrally connected four-cylinder multiples thereof.

The pumps of this invention are very useful for pumping solutionscontaining suspended materials, such as those generally used in weed,livestock, insecticide, and other types of sprays, and for pumpingextremely heavy, slurry-type mixtures. The pumps have acharacteristically smooth high pressure discharge and require littlepower to operate.

It is an object of this invention to provide a compact, eflicient, highpressure, positive displacement, multiple cylinder radial pump.

It is another object of this invention to provide a multiple cylinderradial pump in which the ratio of size and weight to capacity is smalland which can be directly connected to a power source withoutintervening belts, pulleys, or gears to wear out or reduce pumpefliciency.

It is another object of this invention to provide a rugged, highpressure, light weight pump capable of pumping solutions containingsuspended materials including heavy, slurry-type mixtures.

It is another object of this invention to provide a readilymaintainable, four-cylinder radial pump having replaceable cylindersleeves and self-cleaning, self-seating, low inertia valves and in whichthe orientation of parts is such that pump valves and packings can beserviced without disturbing the plumbing or drive arrangement.

It is another object of this invention to provide a radial pump using acompact reciprocating mechanism having a double Scotch yoke with asingle bearing block.

It is another object of this invention to provide in a radial pumputilizing a double Scotch yoke in its reciprocating mechanism a centerloading seeking needle hearing to direct plunger motion in a straightline, thus requiring yokes having strength substantially in a singledirection only.

It is an other object of this invention to provide in a radial pump asingle central crank case for the reciprocating mechanism which isseparated from cylinders and fluid channels so that such reciprocatingmechanism is not contaminated by fluids being pumped.

It is another object of this invention to provide a multiple cylinderradial pump body which can be stacked with similar bodies to provide anumber of difierent pump capacity sizes, each grouping of stacked pumpbodies being driven by a single rotary drive shaft.

Other and further objects of this invention will become apparent tothose skilled in the art upon the reading of the present specificationtaken in conjunction with the attached drawings in which:

FIG. 1 is an end elevational view of a pump of this invention, someparts thereof broken away and some parts shown in section;

FIG. 2 is an elevational view of the opposite end of the embodimentshown in FIG. 1, some parts thereof broken away and some parts shown insection;

FIG. 3 is a view in side elevation of the embodiment shown in FIG. 1,some parts thereof broken away and some parts shown in section;

FIG. 4 is an enlarged view in vertical section taken along the line 44of FIG. 1, some parts thereof shown in elevation and some parts brokenaway;

FIG. 5 is an enlarged diagonal sectional view taken along the line 5-5of FIG. 2, some parts thereof shown in elevation;

FIG. 6 is an enlarged view in horizontal section taken along the line6-6 of FIG. 1, some parts thereof broken away;

FIG. 7 is an enlarged view in vertical section taken along the line 7--7of FIG. 3, some parts thereof shown in elevation and some parts brokenaway;

FIG. 8 is a further enlarged View in horizontal section taken along theline 88 of FIG. 7, some parts thereof broken away;

FIG. 9 is a view in diagonal section similar to FIG. 5 showing two unitsof FIG. 1 in tandem arrangement;

FIG. 10 is an elevational view of the plate insert utilized in thetandem assembly shown in FIG. 9; and

FIG. 11 is a side elevational view of the structure shown in FIG. 10.

Turning to the drawings, there is seen an embodiment of a radial pump ofthis invention, herein designated in its entirety by the numeral 20.Liquid to be pumped is drawn into pump port 22.

The body or casing of pump 20 is conveniently formed of a metal such asaluminum or the like and is fabricated by conventional casting andmachining operations. Thus, the body of pump 20 is seen to consist of amanifold 23, a hub 24, and a block 26, the latter positioned between themanifold 23 and the hub 24. In block 26 is formed the head and baseregion for each of four cylinder portions, a first cylinder portion 27,a second cylinder portion 28, a third cylinder portion 29 and a fourthcylinder portion 30. The axes of these cylinder portions 27, 28, 29 and30 are spaced one from the other at intervals in a common radial planenormal to the pump axis. Secured on block 26, one over the head of eachcylinder portion 27, 23, 29 and 34 by means of suitable bolts 32, arerespective first cylinder head 33, second cylinder head 34, thirdcylinder head 35, and fourth cylinder head 36, respectively. Cylinderheads 33, 34, 35 and 36 are conveniently of metal construction formed bysuitable casting and machining operations.

The cylinder portions 27, 28, 29 and 30 are each formed to receive metaltubing such as sleeve inserts 38. These sleeve inserts 38 (four in all)are held round and stopped by simple casting projections 37 integrallyformed on the block 26. Each replaceable cylinder sleeve insert 38 ispressed into the block 26 through an appropriately formed opening in theradially outer ends (four in all) of cylinder portions 27, 28, 29 and3t) and stops against a shoulder 39 formed in the base region of eachrespective cylinder portion 27, 28, 29 and 30. The sleeve inserts 38 areeach exposed so that each can be re moved by merely removing theappropriate adjacent respective heads 33, 34, 35 and 36 and withdrawingsleeves 33 as with suitable sleeve insert puller (not shown).

The sleeve inserts 38 taken together with the adjoining portions 27, 28,'29 and 30 of the block 26 can be considered to form cylinder blockportions disposed in radially outwardly spaced relation to the axis ofthe block 26, which axis is generally normally positioned with respectto the pump axis. Thus, each pair of opposed cylinder portions 28 and 30is angularly spaced about the pump axis from another pair of opposedcylinder portions 27 and 29.

Formed in each head 33, 34, 35 and 36 and communicating with,respectively, each cylinder portion 27, 28, 29 and 30 is a valve chamber45, 46, 47 and 48, respectively. Each such valve chamber 45, 46, 47 and48 extends laterally outwardly (along the common radial plane) in eitherdirection from the head region of each cylinder portion 27, 28; 29 and30 (see FIG. 7). Integrally formed within block 26 and communicatingwith an opposite end region of each valve chamber 45, 46, 47 and arefour channels or passages 50, 51, 52 and 53, respectively. Each suchchannel 50, 51, 52 and 53' communicates with that face of block 26 whichabuts against the face of manifold 23 in the assembled pump 21 throughrespective ports 55, 56, 57 and 58. Placed circumferentially around eachport 55, 5:, 57 and 53 is an annular groove for Q-ring seals 59 so as toprovide liquid-tight engagement of manitold 23 with block 26.

It will be observed that the ends of each passage 59, 51, 52 and 53 arespaced apart from the block portions comprising the cylinder portions27, 28, 29 and 3t) and that the ends of these passages St), 51, 52 and53 are connected with the head region of each cylinder portion 27, '28,29 and 36 when the heads 33, 34, and 36, respectively, are mounted inplace over the head regions of each cylinder portion 27, 23, 29 and 30,respectively.

Ports 55 and 57, respectively, which are in a side face of block 26,communicate with input port 21 through channels and 61, respectively,which are integrally formed in the manifold 23. Ports 56 and 58communicate with outlet port 2 2; the connection between port 55 andoutlet port 22 being direct (see FIG. 2) while port 57 communicates withoutlet port 22 via channels 63 and 64 which extend within manifold 23circumferentially around rotary drive shaft bearing mount (the latterbeing in tegrally formed in manifold 23), being positioned underchannels 60 and 61 in manifold 23. The channels 63 and 64 join in theirend regions to form common channels 67 and 68, respectively, withchannel 67 connecting port 58 and channel 68 connecting outlet port 22.

Spaced between the ends of channels 50, 51, 52 and 53 and valve chambers45, 46, 47, and 48, respectively, is a series of check valves (eight inall). The check valves at each end of channel 50 are numbered 7tl'and71, respectively; those at the end of channel 51 are numbered 72 and 73;those at the end of channel 52 are numbered 74 and 75 and those ateither end of channel 53 are numbered 76 and 77. Check valves 71 and 72are mounted in a valve plate 80 which is positioned and mounted betweenblock 26 and second cylinder head 34. Check valves 73 and 74 are mountedin a valve plate 81 which is positioned and mounted between block 26 andthird cylinder head 35. Check valves 75 and 76 are mounted in a valveplate 82 which is positioned and mounted between block 26 and fourthcylinder head 36, Check valves 77 and 70 are mounted in a valve plate 83which is positioned and mounted between block 26 and first cylinder head33. Positioned on either side of each valve plate 80, 81, 82 and 83 isan appropriately shaped gasket 84.

The operation of each check valve 70, 71, 72, 73, 74, 75, 76 and 77 isthe same and will now be briefly described by reference to valve 71.Valve 71 has a stem 86 which extends loosely through a circular aperture87 in valve plate 80. A cup-shaped valve element 83 is mounted on oneend of stem 86 so that its convex wall normally seats in the aperture 87on one side of the valve plate 80. A spider support element 89 looselyjournals the stem 86 and is so positioned that its rim portion slidablyengages the opposite side of valve plate 80 adjacent the circularaperture 87. The spokes of spider 59 connect the hub and rim portionsthereof and define ports for fluid passage therethrough. A coiled spring96 circumscribes stem 86 and is compressed between the hub portion ofspider 89 and the concave walls of a cup 91 which is secured over theend hub portion of stem 36 (the end opposite that to which valve element88 is mounted). The spring yieldingly urges the stem 86 in a directionto seat the valve element 88 in aperture 87.

The check valves 70 and 71 are each mounted so as to normally closechannel 50 against the flow of fluid into such channel 50 from the endsbut to pass liquid flow out of the ends of channel into, respectively,valve cham= bers 45 and 46, Thus, fluid entering channel 50 throughports 55 passes to either end of channel 50 and past the respectivecheck valve 7 (l and 71. A similar situation prevails with respect tochannel 52 and the respective check valves 74 and 75 mounted at eitherend thereof. Thus, when fluid enters channel 52 through port 57, it canflow into respective valve chambers 47 and 48 past check valves 74 and75.

However, as respects channel 51, the check valves 72 and 3 at either endthereof prevent liquid from passing out of either end of channel 51;instead, check valves 72 and 73 are here mounted to admit fluid intochannel 51 from, respectively, valve chambers 46 and 47. Thus, fluidenters either end of channel 51 and passes to the midregion thereof toexit therefrom through port 56, Similarly, check valves 77 and 78 ateither end of channel 53 are so mounted as to admit fluid into channel53 from respective valve chambers 45 and 48 (and not vice versa); fluidentering channel 53 being permitted to exit therefrom through port 58.Manifold 23 is secured to block 26 by means of four bolts Q3 which screwinto the face of block 26. Hub 24 is secured to the opposite face ofblock 26 by means of four bolts 94. It will be observed that whenmanifold 23 and hub 24 are mounted upon block 26, as described, thecentral portion or crankcase 96 of block 26 is physically isolated fromthe various channels and ports just described. Even the insert sleeves38 are isolated from crankcase 96 as will be appreciated from thefollowing description.

Rcciprocally moveable in each insert sleeve 38 are, respectively, firstpiston assembly Q8, second piston assembly third piston assembly 1%, andfourth piston assembly 161. The construction of each piston assembly 98,99, 1% and 161 is the same and will now be briefly described byreference to first piston assembly 93. A bolt 103, whose end region isthreaded, has slipped (in this order) over its shank a circular follower164, a first packing cup 165, a top spacer 106, a second packing cup1197, a bottom spacer 198, and finally a plunger 109. The neck region ofplunger 1% slidably engages the shank of bolt 163 and its top end buttsup against the bottom of circular follower 164. The out-turned,oppositely extending outer faces of each packing cup 165 and 167slidably engage the inside wall of each sleeve insert 38. The side ofplunger 169 slidably engages a plunger guide or bushing (such as abronze Oilite bearing). On that side of bushing 110 facing towards thehead end of the piston assembly 98 is positioned a packing 111 (such asa quadring seal and backing washer). Each packing 111 encloses thereciprocating mechanism, herein generally designated by the numeral 114,and seals it in crankcase 96 from the atmosphere and the fluid beingpumped.

Plunger 169 taken together with the shank of bolt 103 can be consideredto form a piston rod which is rigidly connected to a piston which can beconsidered as being formed by circular follower 104, first packing cup105, top spacer 166, and second packing cup 107.

The reciprocating mechanism 114 produces the desired to and fro movementof each piston assembly 98, 99, 190 and 101 slidably within eachrespective insert sleeve 38. The reciprocating mechanism 114 uses a pairof Scotch yokes 115 and 116. Each of these yokes 115 and 1116 consistsin a crossliead portion having an elongated slotted region 117 and 118,respectively, extending lengthwise therethroug'n. The width of each suchregion is such as to accommodate a rotary drive shaft 120 and the lengthis such as to correspond to the distance which each piston moves in itscylinder. The legs 121 and 122 of Scotch yoke 11 and the legs 123 and12d of Scotch yoke 116 each depend normally from opposite end regions ofthe slotted crosshead portion of each such Scotch yoke 115 and 116,respectively. The Scotch yokes 115 and 116 are positioned in crankcase96 so that their rcspective legs oppose one another but are positionednormally with respect one to the other. Shaft 120 extends therethroughrespective slots 117 and 118.

The exposed side face or outside wall of each leg 121, 122, 123 and 124has a threaded aperture (two of which are shown) centrally positionedtherein and each leg pair has these apertures axially aligned. Adjacenteach such aperture 126, 127 on the outside face of each leg 121, 122,123 and 124, respectively, it is a concentrically positioned shoulder12?: and 12 9 (two of which are also shown) whose diameter generallypermits sliding engagement with the inside end wall region of eachplunger 109. The threaded apertures 126 and 127 have respectivediameters and associated threading which permits each bolt 103 ofrespective piston assemblies 98, 99, 1% and 101 to be screwed thereinto,in the manner shown, for example, in FIGS. 7 and 8.

On the inside face of each leg 121, 122, 123 and 124, in an appropriateslot, is mounted a shoe bearing plate 130 (such as a bronze Oilitehearing or the like). Mounted between the inside faces of each leg 121,122, 123 and 124, against the shoe bearing plate 131 and between thespace between the slotted cross-head portions of the Scotch yokes 115and 116, is a square-sided hearing block 131 having a cylindricalaperture out therethrough from face to face. Rigidly mounted on rotarydrive shaft 12d is an eccentric cam element 132 whose outer circularsurface engages needle roller bearings 133 within bearing block 131. Tosecure the eccentric cam element 132 to the drive shaft 121 a keyway isprovided in the eccentric cam 132 with a matching seat in the driveshaft 12% for a \Voodruff key 133. (See FIG. 8.)

When the webs or slotted regions 117 and 118, respectively, or Scotchyokes 115 and 116 are installed at 90 to each other in the axial plane,as described, the square outer race of the needle caring block 131floats between the webs or slotted regions 117 and 118 of the respectiveyokes 115 and 116. The outer race or bearing block 131 provided withneedle bearings 133 rides on the eccentric cam 132, located on the driveshaft 120, as described. The loads impressed on the faces of the outerrace 131 of the needle bearings are always centered on the bearingssince the outer race 131 floats, and a characteristic of a floatingneedle bearing is to seek a position where the load is centered. Thus,the combination of the two Scotch yokes 115 and 116 together with theneedle bearing block 131 and shoes 131i mounted on the eccentric camelement 132 are so operatively connected to each of the piston rods ofthe piston assemblies 93, 99, 1111) and 101, respectively, as to impartradial reciprocatory pumping movements thereto, thereby making thepistons responsive to the rotary movement of the shaft 121?.

In the embodiment shown, the reciprocating mechanism 114- is lubricatedby running it in oil (not shown). In this case open ball bearings 135and 136, respectively (see FIG. 4), are used. Oil enters crankcase 96through the aperture for fill plug 137 in manifold 23. The oil level inthe crankcase 96 is conveniently controlled by level plug 133 which islocated in hub 24. In this method of lubrication, the outer and innerraces for respective ball bearings 13S and 136, respectively, arelubricated by splash action. Observe that shaft 12%) iscircumferentially sealed at the point where it passes through hub 24 bya conventional sealing assembly 142.

Observe that the arrangement of the Scotch yokes 115 and 116 andrespective plungers 109 is such that the plungers 109 can be guidedeither by a guide sleeve 110 placed on the mechanism side of the packing111 or simply by the packing washers 1G5 and 107. The method of guidingthe plungers 1119 is usually determined by the method of lubricationemployed. Instead of being oil lubricated, as in the present embodiment,the mechanism 114 can be lubricated by grease injected into thecrankcase 96 behind the manifold bearing 135 and thence conducted}through a suitable channel in the shaft 120 to the needle roller bearingassembly. In this case the plungers 109 'blies 98, 99, and 161.

are guided by the packing washers and 107 on their respective packingassemblies. The crankcase 96 then runs dry and the seals merely keepforeign material from entering crankcase 96.

Observe that the respective sleeve inserts 38 stop away from the body ofblock 26 against shoulders 42 and 39 so that in the event of a leak pastthe packing cups 105 and 107 the liquid runs away and does not enter thecrankcase 96.

Owing to the construction of a manifold 23, when the reciprocatingmechanism 114 operates in oil, that portion of the manifold 23 whichwould normally serve as the grease cavity is surrounded by water flowingthrough respective channels 63 and 64. In this case, the water serves asa condenser, thereby preventing oil vapor from escaping out of a vent(not shown) provided in fill plug 137, the vent being of conventionaldesign and not a part of this invention. Since the vent is thus locatedin the manifold 23, this arrangement also prevents oil from beingsplashed out of the vent opening. Also, if the pump 20 should becomeinverted in use, the oil cannot run out of the vent.

To position the drive shaft in the desired fixed relationship to thedouble Scotch yoke and to the respective ball bearings 135 and 136, ashoulder 143 is for-med on the drive shaft 120 at such a distance fromthe end thereof as to place the shoulder between eccentric cam 132 andthe inner race of ball bearings 136.

A sleeve 144 slidably engages the forward end of drive shaft 120 andserves as a spacer positioning the eccentric cam 132 the desireddistance from the inner race of the ball bearings 135.

The operation of the reciprocating mechanism 114 is as follows. As theshaft 120 rotates, the eccentric earn 132 causes the bearing block 131to orbit in crankcase 96 about the axis of drive shaft 120. The axis ofthe hearing block 131 is eccentric to the axis of drive shaft 120 but isconcentric with the axis of eccentric cam 132. As the bearing block 131orbits, it slidably moves against the respective surfaces of theindividual bearing surface plates of the respective Scotch yokes 115 and116. Since the yokes are fixed 90 to each other in the axial plane uponthe drive shaft 120, reciprocatory motion is produced of opposed pistonpairs; that is, the first and third piston assemblies 98 and 100,respectively, move in common direction, and the second piston assembly99 and the fourth piston assembly 101 similarly move in common directionwhereby pumping action (i.e., suction and pumping) is simultaneouslyproduced on each stroke of piston pairs 98, 101i and 99, 101.

To assemble radial pump 20 the following procedure can be employed. Hub24 is suitably positioned on shaft 120, the sealing assembly 142 and thebearing 141 being in the desired sliding engagement with the shaft 120.Next, a pump body having a block 26 is positioned over shaft 120, suchpump body having the pistons duly assembled. The next step is toassemble the reciprocating mechanism 114 about the shaft 143, and thenbearing 14% is positioned about the end of shaft 120. Finally, themanifold 23 is mounted on the block 26.

The operation of the pump 20 is as follows: Fluid enters the pump 20through input port 21 in manifold 23, and flows through passages 60 and61 past ports 55 and 57 into channels 50 and 52, respectively, beingdrawn through these respective channels past valves 70, 71, 74 and 75 bythe suction produced by the reciprocatory motion of the pistons 98, 99,100 and 101. After passing the valves 70, 71, 74 and 75, the flow offluid is through the respective valve chambers 45, 46, 47 and 48, andinto the respective channels 56 and 58, respectively, past the valves72, 73, 76 and 77, respectively. Fluid is forced through these valves72, 73, 76 and 77, as explained, by the reciprocatory motion of thepiston assem- After entering opposite ends of the respective channels 51and 53, the fluid passes out F ports 56 and 53 into channels 63 and 64(from port 58) and directly from port 56 to port 22, and finally exitsfrom outlet port 22 into a delivery line.

In FIGS. 9,- and 11 are shown the appearance; of a stack arrangementwherein two pump sections of the type shown in FIGS. 1-8 are axiallyaligned in face to face engagement so as to provide a single pump havingapproximately a little less than twice the output volume at about thesame output pressure as associated with a single pump body. The productassembly involves extending entirely through one block 26' the holes forbolts 94 (four in all) so as to produce a modified block 145. It shouldbe noted that the alternative embodiment of my invention shown in FIGS9-11 and hereinafter described corresponds in all respects notspecifically hereinafter mentioned to the above described embodiment ofmy invention shown in FIGS. 91 1, and the parts or elements of saidalternative embodiment which correspond to like parts or elementsinFIGS. 9l l are denoted by the use of the same reference characterswith prime marks added thereto.

The product assembly also involves modifying a second pump block 26" byextending through block 26" four ports, two of which are shown andidentified by the numerals 56", 58", in axial alignment with ports 56and 58' so as to provide communication for fiuid passage between a pairof pump bodies stacked together. The modified block is indicated by thenumeral 150 in FIG. 9.

Between the opposed faces of each adjoining pair of stacked pumpsections a special spacer plate 146 is mounted. The spacer plate 146 isso made that its rim portion 147 contacts the opposing side faces of apair of blocks 145 and 150, yet the mid-portion 148 has raised faces inthe regionof the crankcase 96'. These raised faces serve to position andaxially align one pump body with respect to another. Port 149 in theraised portion 148 of plate 14-6 serve to permit passage of lubricatingoil from one crankcase 96' to an adjoining crankcase in a stack of pumpsections. It may be noted that plate 146 is provided with apertures 155,156, 157 and 158 which permit communication of ports 56', 58' with ports56", 58", respectively, shown in FIG. 9, through respective apertures156, 158. Apertures 155, 157 communicate with their respective ports(not shown) in a like manner. Also, in order to provide sealingengagement of the face of block 150 which adjoins plate 146, suitablegrooves are conveniently circumferentially placed about each port 56'and 58' for O-ring seals 151.

Broadly, to assemble pump sections into a stack, one begins by firstpositioning a hub 24 on the drive shaft 152 using the same arrangementas for a single pump body. Next, the pump section having the modifiedblock 145 is positioned on shaft 152 in the usual relationship to thehub 24, and then the reciprocating mechanism 114' for the pump sectionof block 145 is assembly in place. The plate 146 is next positioned uponthe other face of 145 (opposite that engaged with the hub 24), therebeing a bearing 154 in plate 146 journalling the shaft 152 in the regionwhere the shaft 152 passes through the plate 146. The bearing 154 isused to take up unbalanced loads between the eccentric earns 1.32 whichare positioned one on either side thereof within the respectivereciprocating mechanisms 114 of each pump body. Next, the pump bodyhaving block 156 is mounted on plate 146 and the reciprocating mechanism114 for that pump body is mounted on the shaft 152. Finally, the bearingassembly 140' is mounted on the shaft 152, and the manifold 23 ismounted on the block 150 to complete the assembly shown in FIG. 9. Theeccentric cams 132 (not shown in FIG. 9) can be spaced 180 with respectto one another on the shaft 152 so as to produce flow characteristicslike that of a single pump. If the eccentric cams 132' are otfset at 135with respect to one another, a resultant smooth flow is achieved.

Three or more pump bodies can be similarly joined together; however, theintermediate pump bodies (not shown) between those pump bodies havingblocks and have the same general construction as that employed in theblock 150 except that the bores for bolts 94' extend all the way throughsuch intermediate pump bodies so that the shanks of bolts 94 are securedto the pump body 15:) while the heads thereof position the hub 24 in thedesired fixed relationship to the block 145. When three or more bodiesare joined together, the intermediate bearings 154 and plates 146 arepositioned between adjacent faces of stacked pump bodies. When threepump bodies are joined together, the cams can be spaced 120 apart toachieve desirable smooth flow characteristics.

My invention has been thoroughly tested and found to be completelysatisfactory for the accomplishment of the above objects, and while Ihave shown and described a preferred embodiment, I wish it to bespecifically understood that the same is capable of modification withoutdeparture from the spirit and scope of the appended claims.

The claims are:

1. A radial pump comprising (a) casing means defining a centralcrankcase and a plurality of cylinders extending radially outwardly fromsaid crankcase in a common plane and arranged in diametrically opposedpairs, each pair being angularly displaced relative to another of saidpairs, a pump chamber at the outer end of each of said cylinders, aninlet port and an outlet port, and inlet and outlet passages connectingeach of said inlet and outlet ports with said chambers,

(12) check valves interposed between said inlet and outlet passages andeach of said pump chambers and operative to admit fluid to said chambersonly from said inlet passages and from said chambers only to said outletpassages,

(c) a plurality of pistons one each axially slidable in a different oneof said cylinders,

(d) a rotary shaft axially journalled in said casing means,

(e) an eccentric element on said shaft,

(1) piston rods rigidly connected to and extending radially inwardlyeach from a different one of said pistons,

(g) means rigidly securing the inner ends of opposed piston rodstogether for common reciprocatory movement of respective opposed ones ofsaid pistons, and operatively connecting said piston rods to saideccentric element, whereby to impart reciprocatory movement to saidpiston rods and pistons responsive to rotary movement of said shaft,

(h) said casing means further defining openings intermediate saidpistons and the radial inner ends of said cylinders and establishingcommunication between said cylinders and the exterior of said casingmeans, and

(i) sealing means in each of said cylinders intermediate said openingsand the radial inner ends of said cylinders.

2. A radial pump comprising (a) a casing defining a central crankcaseportion and diametrically opposed pairs of cylinder block portionsdisposed in radially outwardly spaced relation to said crankcaseportion, one pair of said opposed block portions being angularly spacedabout the axis of said casing from another pair of opposed blockportions, spaced apart inlet and outlet passages connecting the blockportions of each of said pairs with the block portions of adjacent pairsthereof,

(b) cylinder heads on the radially outer ends of said block portions andcooperating therewith to define pump chambers,

(0) end members at opposite ends of said casing,

(d) one of said end members having an inlet port communicating with saidinlet passages,

(e) one of said end members having an outlet port communicating withsaid outlet passages,

(1) check valves in said inlet passages for admitting fluid to said pumpchambers and in said outlet passages for discharge of fluid from saidpump chambers,

(g) each of said block portions having a radial bore intermediate itsrespective inlet and outlet passages and communicating with itsrespective pump chamber and said crankcase,

(h) a cylinder in each of said bores, said cylinders terminating attheir radially inner ends in radially outwardly spaced relation to saidcrankcase,

(i) a plurality of pistons each slidably mounted in a different one ofsaid cylinders,

(j) rigid piston rods rigidly connected at opposite ends todiametrically opposed pairs of said pistons,

(k) a rotary shaft extending axially of said crankcase and journalled insaid end members,

(I) an eccentric element on said shaft in said crankcase,

(in) means on said eccentric element operatively connected to saidpiston rods for imparting radial reciprocatory pumping movements theretoand to said pistons responsive to rotary movement of said shaft,

(n) said casing having an opening radially inwardly of each of saidcylinders communicating with the exterior of said casing, and

() bearing and sealing means mounted in each of said bores between saidopenings and the radially inner ends of said bores and slidablyencompassing adjacent portions of said piston rods.

3. The structure defined in claim 2 in which said casing defines aradially outwardly facing arcuate shoulder in each of said bores, saidshoulders being disposed radially outwardly of said openings andproviding seats for the inner ends of said cylinders.

4. The structure defined in claim 3 in which the block portions of saidcasing comprise tubular elements which define portions of said inlet andoutlet passages, the outer surfaces of said cylinders being exposedintermediate their ends between said tubular elements.

5. A radial pump comprising:

(a) casing means defining, a central crankcase, a pair ofcircumferentially spaced radial cylinders disposed radially outwardly ofsaid crankcase, a pump chamber at the outer end of each of saidcylinders, an inlet port and an outlet port, and inlet and outletpassages connecting each of said inlet and outlet ports with saidchambers,

(b) check valves interposed between said inlet and outlet passages andeach of said pump chambers and operative to admit fluid to said chambersonly from said inlet passages and from said chambers only to said outletpassages,

(c) a pair of pistons one each mounted in a difierent one of saidcylinders for axial reciprocation therein,

(d) a drive shaft journalled in said crankcase and extending axiallythereof,

(e) an eccentric element fast on said drive shaft,

(1) a pair of piston rods each rigidly connected to a different one ofsaid pistons and operatively connected to said eccentric element forimparting reciprocatory movement to said pistons responsive to rotarymovement of said drive shaft,

(g) said crankcase and the inner ends of said cylinders definingopenings between the inner ends of said cylinders and the exterior ofsaid crankcase,

(h) and sealing means for said piston rods and crankcase radiallyinwardly of said openings for sealing the interior of said crankcasefrom the exterior thereof.

6. The structure defined in claim 5 in which said cylinders comprisesleeve-like cylinder elements, and in which said casing defines, a pairof radial bores outwardly spaced from said crankcase for receiving andsupporting the outer end portions of said cylinder elements, andcircumferentially spaced shoulders exterior of said crankcase forsupporting the inner ends of said cylinder elements.

References Cited by the Examiner UNITED STATES PATENTS 860,826 7/07Reavell 230-187 1,032,603 7/ 12 Hayner 230--187 FOREIGN PATENTS1,189,629 3/59 France. 1,096,750 1/61 Germany.

LAURENCE V EFNER, Primary Examiner.

JOSEPH H. BRANSON, 111., Examiner.

1. A RADIAL PUMP COMPRISING (A) CASING MEANS DEFINING A CENTRAL CRANKCASE AND A PLURALITY OF CYLINDERS EXTENDING RADIALLY OUTWARDLY FROM SAID CRANKCASE IN A COMMON PLANE AND ARRANGED IN DIAMETRICALLY OPPOSED PAIRS, EACH PAIR BEING ANGULARLY DISPLACED RELATIVE TO ANOTHER OF SAID PAIRS, A PUMP CHAMBER AT THE OUTER PORT, AND INCYLINDERS, AN INLET PASSAGES CONNECTING EACH OF SAID INLET LET AND OUTLET PASSAGES CONNECTING EACH OF SAID INLET AND OUTLET PORTS WITH SAID CHAMBERS, (B) CHECK VALVES INTERPOSED BETWEEN SAID INLET AND OUTLET PASSAGES AND EACH OF SAID PUMP CHAMBERS AND OPERATIVE TO ADMIT FLUID TO SAID CHAMBERS ONLY FROM SAID INLET PASSAGES AND FROM SAID CHAMBERS ONLY TO SAID OUTLET PASSAGES, (C) A PLURALITY OF PISTONS ONE EACH AXIALLY SLIDABLE IN A DIFFERENT ONE OF SAID CYLINDERS, (D) A ROTARY SHAFT AXIALLY JOURNALLED IN SAID CASING MEANS, (E) AN ECCENTRIC ELEMENT ON SAID SHAFT, (F) PISTON RODS RIGIDLY CONNECTED TO AND EXTENDING RADIALLY INWARDLY EACH FROM A DIFFERENT ONE OF SAID PISTONS, (G) MEANS RIGIDLY SECURING THE INNER ENDS OF OPPOSED PISTON RODS TOGETHER FOR COMMON RECIPROCATORY MOVEMENT OF RESPECTIVE OPPOSED ONES OF SAID PISTONS, AND OPERATIVELY CONNECTING SAID PISTON RODS TO SAID ECCENTRIC ELEMENT, WHEREBY TO IMPART RECIPROCATORY MOVEMENT TO SAID PISTON RODS AND PISTONS RESPONSIVE TO ROTARY MOVEMENT OF SAID SHAFT, (H) SAID CASING MEANS FURTHER DEFINING OPENINGS INTERMEDIATE SAID PISTONS AND THE RADIAL INNER ENDS OF SAID CYLINDERS AND ESTABLISHING COMMUNICATION BETWEEN SAID CYLINDERS AND THE EXTERIOR OF SAID CASING MEANS, AND (I) SEALING MEANS IN EACH OF SAID CYLINDERS INTERMEDIATE SAID OPENINGS AND THE RADIAL INNER ENDS OF SAID CYLINDERS. 